To date, Jem Cohen has made intimate non-fiction diary films rooted in an attentiveness to atmosphere and riddled with small observations rendered in profound terms. While his new feature “Museum Hours” is technically his first narrative effort, with a pair of amateur performances and the backbone of a fictional story, its constant introspection and remarkable sense of place provide a fluid connection to the earlier work. With a keen eye for the capacity of fine art to address a complex range of attitudes and experiences, “Museum Hours” effectively applies Cohen’s existing strengths to a familiar scenario and rejuvenates it by delivering a powerfully contemplative look at the transformative ability of all art.

On the one hand a sad, poignant character study, “Museum Hours” is also a treatise on art history and a love letter to architectural wonder. Predominantly set in Vienna’s grand Kunsthistorisches Art Museum, the trim story involves middle-aged museum guard Johann (Robert Sommer, making a gently affecting onscreen debut), whose quiet gig has allowed him to fade into his surroundings and observe the visitors in much the same way they peer at the artwork. It’s here that he encounters the distant Anne (Canadian songwriter Mary Margaret O’Hara), a woman of the same generation who’s in town to deal with her cousin’s debilitating illness. Sensing Anne’s isolation in the big city, a physically overwhelming sensation that reflects her inner turmoil, Johann quickly forms a bond with the woman and keeps her company around town.

A soft-spoken gay man whose lover died years earlier, Johann copes with a similar estrangement from his surroundings and confesses to spending his free time at home playing online poker. Over the course of extensive conversations, however, their personalities emerge with sharp definition, as they talk about music, career paths and life philosophies. Their ongoing dialogue maintains an engaging stream-of-consciousness quality reminiscent of “Before Sunrise” and “Before Sunset,” both of which involve two soul-searching individuals from separate cultures who bond through mutual self-analysis. But the connection between Johann and Anne is only one component of “Museum Hours,” which branches out to explore the crevices of the Kunsthistorisches and the ability of its contents to address a multitude of ideas.

In the voiceover narration he provides throughout the film, Johann decries “the transience of things,” which is the closest thing “Museum Hours” has to a villain. Johann finds the cure for this destructive impulse, epitomized at one point by a bored visitor yanking out his cell phone during a tour, in the immutable splendor of the museum’s collection. As he and Ann find solace in the ancient, timeless beauty of centuries-old paintings, “Museum Hours” casually deviates from its central tale and allows aesthetic worship to dominate the mood. In short, having established its narrative base, “Museum Hours” becomes a Jem Cohen movie.

Johann’s conviction that museum visitors treat him as invisible, allowing him to monitor closely their investment in the collection, invites an immediate connection to Cohen’s “Lost Book Found,” in which the filmmaker recalls feeling invisible during his days as a food cart vendor. As Johann blends with his surroundings, the museum takes over, its majestic archways and high ceilings forming a wordless poem. Still, in spite of such ostentatious displays, “Museum Hours” retains its humanity, and even breaks its serious pose for flashes of humor (as when Johann notes that he’s asked for bathroom directions more than anything else).

Cohen’s discursive approach veers in and out of reality with a seamless rhythm. At one point, an inconsequential shot of the gallery turns surreal when the visitors suddenly appear naked, showing the paintings’ transformative impact on the spectator. At other times, the movie takes a detour into art history, using a discourse on style to explore the central themes. An extensive lecture by a museum guide on the nuances of Flemish Renaissance painter Pieter Bruegel, with particular focus on his vibrant New Testament image “The Procession to Calvary,” draws out the details of the frame that stretch far beyond the beleaguered messiah at its center. Such foregrounding of seemingly inconsequential minutiae connects an aesthetic several hundred years old to the process of environmental submersion that defines Cohen’s approach.

Although its winding trajectory can come across as sleepy and even lethargic, the casual pace heightens the serene atmosphere just as the assortment of conversational pathways enhances the movie’s intellectual appeal, ensuring that it never devolves into a prototypical death drama. Eventually, because of the pieces set in place early on, it must arrive at a climax that involves both characters and the fate of Anne’s cousin. However, it only gets to this point once an intricate mood has been established.

The emotion of the finale is connected to larger truths but not at the expense of its human personalities. Summer and O’Hara’s fragile, insinuative performances foreground their repressed dramas. Whether seeking meaning in paintings or their lives, their faces reach artistic heights worthy of the same scrutiny allotted to the museum’s collection.

Criticwire grade: A-

HOW WILL IT PLAY? “Museum Hours” opens this week in New York ahead of several other markets. Despite its limited appeal, strong reviews and word of mouth may help draw in the older demographic of arthouse audiences.